We examined the impact of Lactobacillus casei subsp. casei 327 (Lc327) on colonic production of serotonin (5-hydroxytryptamine, 5-HT), a critical regulator of gastrointestinal (GI) function. Heat-killed form of Lc327 was orally administered to BALB/c mice for 14 consecutive days. Significantly higher amounts of 5-HT were detected in colonic tissues from Lc327 group mice compared to control mice. Immunohistochemistry assays revealed that significantly higher frequency of the cells containing 5-HT markedly in colon from Lc327 group mice. In accordance with these findings, elevation in relative mRNA levels for tryptophan hydroxylase 1, the rate-limiting enzyme for mucosal 5-HT, was observed in colonic epithelium from Lc327 group mice. Additionally, oral administration of heat-killed Lc327 shortened the transit time of colonic bead expulsion in mice. These results suggest that the heat-killed Lc327 has a potential to promote 5-HT synthesis in colonic mucosa, which could contribute to improving GI motility.

我们检查了干酪乳杆菌亚种的影响。凯西327（Lc327）关于结肠产生5-羟色胺（5-羟色胺，5-HT）的作用，5-羟色胺是胃肠道（GI）功能的关键调节剂。将热杀死的Lc327形式连续14天口服给予BALB / c小鼠。与对照小鼠相比，在Lc327组小鼠的结肠组织中检测到大量的5-HT。免疫组织化学分析显示，来自Lc327组小鼠的结肠中含有5-HT的细胞的频率明显更高。根据这些发现，在Lc327组小鼠的结肠上皮中观察到了色氨酸羟化酶1（粘膜5-HT的限速酶）的相对mRNA水平的升高。此外，口服热灭活的Lc327可以缩短小鼠结肠珠排出的时间。